Explanation:
A mere 30 million light-years away, large spiral
galaxy NGC 3628 (center left) shares
its
neighborhood in the local Universe with
two other large spirals, in a
magnificent grouping otherwise known as
the Leo Triplet.
In fact, fellow trio member
M65 is near the center right edge of this deep cosmic group portrait,
with M66 just above it and to the left.
But, perhaps most intriguing
is the spectacular tail stretching down
for about 300,000 light-years from
NGC 3628's warped, edge-on disk.
Known as a
tidal tail, the structure has been drawn
out of the galaxy by gravitational tides during
brief but
violent past interactions with
its large neighbors.
Not
often imaged so distinctly, the tidal tail is
composed of young bluish star clusters and star-forming regions.